.collection-container {
    min-height: 100vh;
    position: relative;
    color: #2c3e50;
  }
  
  .header-background {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 300px;
    background: linear-gradient(135deg, #6a11cb, #2575fc);
    z-index: -1;
    overflow: hidden;
  }
  
  .header-background::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1440 320"><path fill="white" fill-opacity="0.1" d="M0,224L48,218.7C96,213,192,203,288,170.7C384,139,480,85,576,85.3C672,85,768,139,864,176C960,213,1056,235,1152,213.3C1248,192,1344,128,1392,96L1440,64L1440,320L1392,320C1344,320,1248,320,1152,320C1056,320,960,320,864,320C768,320,672,320,576,320C480,320,384,320,288,320C192,320,96,320,48,320L0,320Z"></path></svg>');
    background-repeat: no-repeat;
    background-position: center bottom;
    opacity: 0.3;
  }
  
  .content-wrapper {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
  }
  
  .collection-header {
    padding: 40px 0;
    text-align: center;
    color: white;
  }
  
  .collection-header h1 {
    font-size: 3em;
    margin-bottom: 30px;
    position: relative;
    display: inline-block;
  }
  
  .collection-header h1::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 4px;
    background: white;
    border-radius: 2px;
  }
  
  .collection-stats {
    display: flex;
    justify-content: space-between;
    gap: 20px;
    margin: 20px 0 30px;
    padding: 0 10px;
  }
  
  .stat-card {
    flex: 1;
    background: rgba(255, 255, 255, 0.9);
    border-radius: 15px;
    padding: 20px;
    display: flex;
    align-items: center;
    gap: 15px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    border: 1px solid rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
  }
  
  .stat-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
  }
  
  .stat-icon {
    width: 50px;
    height: 50px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    color: white;
  }
  
  .stat-icon.total {
    background: linear-gradient(135deg, #6366f1, #8b5cf6);
  }
  
  .stat-icon.rare {
    background: linear-gradient(135deg, #3b82f6, #2dd4bf);
  }
  
  .stat-icon.legendary {
    background: linear-gradient(135deg, #f59e0b, #ef4444);
  }
  
  .stat-icon.sets {
    background: linear-gradient(135deg, #10b981, #059669);
  }
  
  .stat-content {
    flex: 1;
  }
  
  .stat-value {
    font-size: 28px;
    font-weight: bold;
    color: #1f2937;
    line-height: 1.2;
    margin-bottom: 5px;
  }
  
  .stat-label {
    font-size: 14px;
    color: #6b7280;
    font-weight: 500;
  }
  
  .progress-card,
  .series-card {
    margin-bottom: 30px;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
    overflow: hidden;
  }
  
  .card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-weight: bold;
    font-size: 1.2em;
  }
  
  .series-filters {
    display: flex;
    gap: 10px;
  }
  
  .search-input {
    width: 200px;
  }
  
  .collection-progress {
    padding: 20px 0;
  }
  
  .progress-levels {
    position: relative;
    padding: 20px 0;
  }
  
  .reward-level {
    display: flex;
    align-items: center;
    margin-bottom: 40px;
    position: relative;
  }
  
  .reward-level:last-child {
    margin-bottom: 0;
  }
  
  .reward-icon {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: #f0f0f0;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2;
    transition: all 0.3s;
    border: 2px solid #e0e0e0;
  }
  
  .reward-icon.glow {
    background: #2575fc;
    border-color: #6a11cb;
    color: white;
    box-shadow: 0 0 15px rgba(106, 17, 203, 0.5);
  }
  
  .reward-line {
    position: absolute;
    top: 20px;
    left: 20px;
    height: 60px;
    width: 2px;
    background: #e0e0e0;
    z-index: 1;
  }
  
  .reward-line.achieved {
    background: #2575fc;
  }
  
  .reward-info {
    margin-left: 30px;
    padding: 15px;
    background: #f5f7fa;
    border-radius: 10px;
    flex: 1;
    transition: all 0.3s;
  }
  
  .reward-level.achieved .reward-info {
    background: linear-gradient(135deg, #f0f4ff, #e4f1fe);
    box-shadow: 0 3px 10px rgba(37, 117, 252, 0.1);
  }
  
  .reward-title {
    font-weight: bold;
    margin-bottom: 5px;
    font-size: 1.1em;
  }
  
  .reward-requirement {
    color: #666;
    margin-bottom: 15px;
    font-size: 0.9em;
  }
  
  .treasure-series {
    margin-bottom: 30px;
    border-bottom: 1px solid #eee;
    padding-bottom: 30px;
  }
  
  .treasure-series:last-child {
    border-bottom: none;
    margin-bottom: 0;
  }
  
  .series-info {
    margin-bottom: 20px;
  }
  
  .series-info h3 {
    display: flex;
    align-items: center;
    margin-bottom: 10px;
  }
  
  .series-progress {
    margin-left: 10px;
    font-size: 0.8em;
    color: #666;
    font-weight: normal;
  }
  
  .series-complete {
    margin-top: 10px;
    display: flex;
    align-items: center;
    gap: 10px;
  }
  
  .treasure-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 20px;
  }
  
  .treasure-card {
    border-radius: 10px;
    overflow: hidden;
    background: #f5f7fa;
    transition: all 0.3s;
    position: relative;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.05);
    height: 100%;
    display: flex;
    flex-direction: column;
  }
  
  .treasure-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
  }
  
  .treasure-card.owned {
    background: white;
  }
  
  .treasure-card.rare {
    border-left: 3px solid #409EFF;
  }
  
  .treasure-card.epic {
    border-left: 3px solid #E6A23C;
  }
  
  .treasure-card.legendary {
    border-left: 3px solid #F56C6C;
    background: linear-gradient(135deg, #fff6f6, #fff);
  }
  
  .treasure-image {
    position: relative;
    padding-top: 100%;
    background: #f0f0f0;
  }
  
  .treasure-image img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
  }
  
  .treasure-info {
    padding: 15px;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
  }
  
  .treasure-info h4 {
    margin: 0 0 8px 0;
    font-size: 0.9em;
  }
  
  .treasure-rarity {
    margin-top: auto;
  }
  
  .owned-badge {
    position: absolute;
    top: 5px;
    right: 5px;
    background: #67C23A;
    color: white;
    width: 25px;
    height: 25px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
  }
  
  .lock-icon {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.6);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.5em;
  }
  
  @media (max-width: 768px) {
    .collection-stats {
      flex-wrap: wrap;
      gap: 15px;
    }
    
    .stat-card {
      flex: 1 1 calc(50% - 15px);
      min-width: calc(50% - 15px);
    }
  }
  
  @media (max-width: 480px) {
    .stat-card {
      flex: 1 1 100%;
    }
    
    .stat-icon {
      width: 40px;
      height: 40px;
      font-size: 20px;
    }
    
    .stat-value {
      font-size: 24px;
    }
  }